I. Definition

  1. Dislocation at MCP
  2. MCP Dislocation is most often at thumb
  3. Dorsal MCP Dislocation is most common

II. Types of Metacarpal-phalangeal (MCP) Dislocation

  1. Simple Dislocation
    1. Dislocation without interposed soft tissue
  2. Complex Dislocation
    1. Soft tissue interposed in the joint
    2. Requires surgical reduction

III. Management: Simple Dislocation

  1. Reduction (dorsal dislocation)
    1. Flex wrist
    2. Hyperextend dislocated joint as far as possible
    3. Push base of proximal phalanx distally
    4. Bring joint back into flexion while pushing base
    5. Avoid simple traction (risk of complex dislocation)
  2. Post-reduction joint assessment
    1. Assess joint range of motion
    2. Assess collateral ligaments with MCP flexed
    3. Imaging to assess joint congruity
  3. Immobilization for 3 weeks
    1. Early range of motion and strengthening in uncomplicated dislocations
    2. Direction of dislocation
      1. Dorsal dislocation: Splint 20-30 degrees of flexion
      2. Volar dislocation: Splint to maintain extension
        1. Discuss with local orthopedic consultants
    3. Finger involved
      1. Thumb MCP Dislocation: Cast thumb for 3 weeks
      2. Finger MCP Dislocation: Buddy tape for 3 weeks

IV. Management: Complex Dislocation

  1. Reduction usually impossible by closed method
    1. Joint does not snap back into place
    2. Joint does not feel reduced
    3. Reduction prevented by soft tissue in joint
  2. Surgery usually needed
    1. Open reduction and internal fixation (ORIF)

Images: Related links to external sites (from Google)